This is the second major divestiture for AMS in the past six months. The Minnetonka-based company sold its Ovion sterilization technology to Mountain View, Calif.-based Conceptus Inc. for $23.6 million last October.

Haunted by her husband’s death, Marie Johnson, an engineer who now directs the University of Minnesota Medical Devices Fellowship program, is developing a low-cost acoustic device that primary care doctors can use to spot potential heart trouble.

The director of the University of Minnesota’s Medical Device Center Fellows program developed algorithms and signal processing techniques used in detecting and analyzing abnormal heart beats. The resulting system, a juiced-up stethoscope made by Maplewood-based 3M Cos. and data-crunching software created by Zargis Medical Corp. was named Innovation of the Year by Popular Science magazine.

The Littmann 3200, records and can store heart, lung and other body sounds and has ambient noise reduction capabilities. But it also has Bluetooth wireless technology that can send data to a computer. It also comes with software equipped with a series of algorithms to analyze the sounds.